Variable automatic speed regulator



March 2, 1965 F. M. BEEGLE 3,171,394

VARIABLE AUTOMATIC SPEED REGULATOR Filed July 31. 1961 2 Sheets-Sheet 1 FI6.I

INVENTOR. FRANCIS M. BEEGLE 289 BY 4: MJ; z:

March 2, 1965 F. M. BEEGLE 3,171,394

VARIABLE AUTOMATIC SPEED REGULATOR Filed July 51. 1961 as as 53 2 Sheets-Sheet 2 FIG. 4

20! I99 37 IN VEN TOR. FRANCIS M. BEEGLE BY HZ United States Patent 3,171,394 VARHABLE AUTQMATH? SPEED REGULATOR Francis M. Beagle, 1179 Dahridge Drive, Memphis, Tenn.

Filed July 31, 1961, Ser. No. 128,093, s Claims. (or. 123-402 This invention relates generally to a speed control mechanism and, more particularly, to a variable device for automatically controlling the speed of a vehicle engine having a fuel throttle or accelerator. The present in vention constitutes an improvement over the device shown in my application Serial No. 745,520, filed June 30, 1958 and now abandoned.

The present invention is directed towards providing automatic speed regulation for vehicles having internal combustion engines, and when adapted to the conventional accelerator mechanism, this device will permit the operator to remove his foot from the accelerator pedal, after he has transferred the control of the accelerator to the automatic device.

One of the objects of the present invention is to provide a speed regulator which is adapted to be used with the accelerator mechanism of motor vehicles to control the fuel fed to the motor.

A further object is to provide such a regulator which permits the accelerator to be held in a pre-selected position when the driver closes a push-button switch to establish a circuit in the electro-magnetic coil of the regulator and depresses the accelerator pedal to a point corresponding to the selector setting.

A further object is to provide such a device which permits the accelerator to be released from a held position when the push-button switch is again closed, and again establishes the control circuit effective to hold the accelerator at the previous pre-selected position when the accelerator pedal is again depressed. a

A further object is to provide such a device which permits the accelerator to be released from a held position when the brake pedal is depressed, whereupon the circuit in the holding device becomes de-energized and remains de-energized until such time as the driver elects to reenergize the electro-magnetic coil of the holding device, as by again closing the push-button switch.

A further object is to provide such a device which. permits the accelerator to be used in the usual manner when the holding means of the present invention is deenergized or otherwise released.

A further object is to provide such a device which permits the accelerator to be advanced in a speed in creasing direction without having to release or otherwise manipulate the accelerator holding device and, further, to allow the accelerator to return to its previously held position when the need for additional power has ended.

A further object is to provide such a device which permits the accelerator to be held at the same relative position on each and every engagement of the holding device or until a new point of engagement is selected.

A further object is to provide such a device which permits the selection of a new rate of speed without having to disengage the holding means.

A further object is to provide in such a device a unique speed sensor which responds to the change in the rate of speed of the engine.

A further object is to provide in such a device a speed selector, which operates on the hydraulic principle, and which is operably coupled to the speed sensor for the control thereof.

A further object is to provide in such a device a unique actuator for positioning the accelerator mechanism to control the fuel in a manner that will permit the engine 3,l7l,394 Patented Mar. 2, 1965 ice to develop power at a rate suflicient to maintain the speed of the vehicle substantially the same as predetermined by the speed selector setting.

A further object is to provide in such a device means for preventing over-controlling action of the speed sensor.

A further object is generally to improve the design and construction of automatic speed regulators.

The means by which the foregoing and other objects of the present invention are accomplished and the manner of their accomplishment will be readily understood from the following specification upon reference to the accompanying drawings, in which:

FIG. 1 is a fragmentary perspective view of a part of the interior of an automobile with parts broken away for purposes or" illustration and showing the control mechanism of the present invention in use therewith.

FIG. 2 is a schematic diagram of the circuit means of the present invention.

FIG. 3 is a fragmentary view of the brake operated switch shown in engagement with the brake arm.

FIG. 4 is a somewhat diagrammatic view of the auto matic speed regulating system of the present invention, With some of the components being broken away for purposes of illustration and some of the components being shown in section with the sections being taken as on vertical planes through the longitudinal center line of the components.

Referring now to the drawings in which the various parts are indicated by numerals, in FIG. 1 is shown a conventional floor board 11 of an automobile with the conventional accelerator pedal 13 pivotally connected thereto as at 15. Linkage means is provided for con-. necting pedal 13 to the usual lever 17 which is fixedly attached to the shaft upon which the usual butterfly valve 19 is mounted. Said linkage means is of any Suitable type with one form thereof being shown in the drawings wherein it will be seen a rod 21 is connected adjacent the upper end of pedal 13 and extends downwardly to its points of hinged connection with one arm of a crank 23 pivotally mounted in brackets 25, the other arm of which is pivotally conected to a rod 27 that extends to the lever 17 and is pivotally connected thereto. A spring 29 is interposed between a fixedly mounted post 31 and lever 17 to urge the lever towards a counterclockwise or speed decreasing direction. It will be understood that, in order to increase the speed, the driver must depress accelerator pedal 13 to urge lever 17 in a clockwise or speed increasing direction. Although the above described conventional accelerator means is of the, type in which rod 27 moves lengthwise to control the throttle, it will be understood that the present invention is equally adaptable to automobiles having accelerator means which rotate to control the throttle rather than moving lengthwise. Also, it will bev understood that the term, throttle or accelerator, applies to the overall existing or usual means for controlling the speed of the automobile including pedal 13, butterfly Valve 19, lever 17 and said linkage means connecting pedal 13 to lever 17, whereas accelerator pedal 13 applies specifically to the pedal only.

The speed regulator 33 of the present invention comprises, in general, five principal parts, namely: (1) a speed sensor 35 which is responsive to the speed of the engine, (2) a speed selector 37 for selecting the desired speed and which speed selector is operably coupled to the speed sensor 35, (3) an actuator 39 for positioning the accelerator mechanism to control the fuel in a manner that will permit the engine to develop power at a rate suificient to maintain the. speed of the vehicle substantially the same as predetermined by the setting of speed selector 37, (4) an electromagnetic coupler 41 which is actually built into the actuator 3% and forms a part thereof, and (5) an electrical control circuit 43 for setting up a magnetic field in the magnetic coupler 41 when the speed regulator 33 is in operation and for discharging the field when the need for conventional operation of the accelerator mechanism occurs.

. Referring now more specifically to actuator 39 and coupler 41, the construction of these parts is described as follows: An electro-magnetic coil 45 is disposed around a sleeve 47 with the sleeve extending axially of the coil and beyond the ends thereof. Coil 45 is preferably provided with an insulated inner casing 49 and an outer housing 51 with sleeve 47 passing through central openings in the opposite ends of casing 49 and housing 51. Coil housing 51 is fixedly attached to an inclosed diaphragm housing, which is indicated in general as at 53, by suitable means, as screw 55 or the like. A substantially disc-like retainer 57 is held in place between coil housing 51 and diaphragm housing 53 and extends inwardly in surrounding relationship to sleeve 47 where it contacts a flange 59 provided on the sleeve to hold the sleeve and coil housing in place. Diaphragm housing 53 is preferably formed in two halves 61, 63 held to 'gether by screws 65 or the like. A substantially circular and flexible actuating diaphragm 67 is fastened adjacent its outer periphery between halves 61 and 63 and extends inwardly towards the center of diaphragm housing 53 where it surrounds one end of an inner plunger or diaphragm follower 69 to which it is fixedly attached as by means of a nut 71 threadedly engaged on the threaded end of diaphragm follower 69 to anchor the diaphragm against a shoulder 73 on the diaphragm follower. Diaphragm 67 divides the interior of housing 53 into a head chamber 75 and a vented chamber 77, which is vented to the outside atmosphere through port 79 in diaphragm housing half 63. The end 81 of diaphragm follower 69 that is remote from diaphragm 67 is slidably received in the bore 82 of sleeve 47. An axial socket 83 is provided in diaphragm follower 69 opening into head chamber 75 and which receives one end of a compression spring 85 which has its opposite end seated against diaphragm housing half 61 to urge the diaphragm follower to the right, as viewed in FIG. 4.

An outer plunger 87 is slidably mounted in the opposite end of sleeve 47 from inner plunger 69 for movement longitudinally into and out of abutment with inner plunger 69. Thus, when plungers 69, 87 are in abutment, the end 89 of outer plunger 87 is in engagement with the end 81 of inner plunger 69.

Plunger 87 is provided with a chamber 93 disposed centrally of the plunger and opening outwardly therefrom adjacent the outer end of the plunger. A follower 95 is slidably mounted in chamber 93 for sliding movement longitudinally of the chamber. Inner plunger 69, bore 82, outer plunger 87, chamber 93 and follower 95 are preferably circular in cross section, but may be shaped otherwise without departing from the spirit and scope of the present invention. A retaining ring 97 is removably mounted in an annular groove in the wall of chamber'93 adjacent the outer end thereof. The outside diameter of follower 95 is greater than the inside diameter of retaining ring 97, whereby the retaining ring limits outward movement of the follower and prevents the follower from being removed from chamber 93. Resilient means, as a compression spring 99, is disposed in chamber 93 between the end wall 101 of chamber 93 and follower 95 to urge the follower outwardly into abutment with retaining ring 97.

Follower 95 is preferably integrally formed in the shape of a flange on a rod 103 which extends outwardly therefrom through retaining ring 97. The end of rod 103 which is remote from follower 95 is connected to lever 17 by suitable linkage means. A preferable form of said linkage means is best shown in FIG. 4, wherein it will be seen the linkage means includes a neck portion 105v and a stud portion 107 pivotally connected to the neck portion as by means of a conventional ball and socket arrangement designated as at 109. Neck portion is connected to rod 103 as by an internally threaded socket 111 in the neck portion threadedly engaged on the externally threaded end 113 of rod 103. Stud portion 107 is connected to lever 17 as by the threaded portion 115 of stud 107 extending through an aperture in the lever and a nut 117 threadedly engaged on the threaded portion 115, as best shown in FIG. 1.

Actuator 39 heretofore described is anchored onto a suitable portion of the automobile, as, for example, onto the motor 119 by a bracket 121 fixedly mounted on housing 51, which bracket in turn is fixedly attached to motor 119 by suitable well-known means.

Referring now more specifically to speed sensor 35, the speed sensor comprises a housing assembly 123 preferably made up of substantially annular parts 125, 127, 129, 131 and 133 which are fixedly held together by suitable means as screws or the like to establish the enclosed housing 123. A plurality of substantially circular diaphragms are spaced apart in housing assembly 123 to divide the housing assembly into a plurality of chambers. Each of the diaphragms are preferably circular and are held adjacent the outer peripheries thereof by parts of housing assembly 123 and extend inwardly towards the center of the housing assembly where each of the diaphragms are fixedly attached to a diaphragm follower 135, which is preferably formed of a plurality of parts 137, 139, 141, 143 and 144. Specifically, the above mentioned diaphragms comprise the following: An operating flexible diaphragm 145 is clampingly held adjacent the outer periphery thereof between housing parts and 127 and extends inwardly to diaphragm follower where it is clamped between a flange 147 on the end of diaphragm part 137 by means of diaphragm part 139 which is in the form of a nut threadedly engaged on a threaded portion of part 137. A first chamber separating flexible diaphragm 149 is clamped adjacent the outer periphery thereof between housing assembly parts 127 and 129 and extends inwardly to the diaphragm follower 135 where it is clamped between the diaphragm follower parts 137 and 141, with these parts being held together as by means of a threaded stud portion151 on diaphragm follower part 141 threadedly engaged in a threaded socket 153 in the end of diaphragm part 137. A second chamber separating flexible dia-' phragm 155 is clampingly held adjacent its outer periphery between housing assembly parts 129 and 131, and the diaphragm extends inwardly to diaphragm follower 135 where it is clampingly held between diaphragm follower parts 141 and 143, with the part 143 being in the form of a nut threadedly engaged on a reduced threaded stud portion 157 ,of diaphragm follower part 141. A compensating flexible diaphragm 159 is clampingly held adjacent the outer periphery thereof between housing assembly parts 131 and 133 and extends inwardly to diaphragm follower 135 where it is clampingly held between diaphragm follower parts 143 and 144 which are both threadedly engaged on stud portion 157 with the stud portion extending upwardly beyond part 144. Diaphragms 145, 149, 155 and 159 divide the interior of housing assembly 123 into the following chambers: A lower chamber 161 in the housing assembly below operating diaphragm 145; a hydraulic chamber 163 between operating diaphragm 145 and chamber separating diaphragm 149; a vacuum chamber 165 between chamber separating diaphragms 149 and 155; an atmospheric chamber 167 between chamber separating diaphragm 155 and compensating diaphragm 159; and a compensating chamber 169 in housing assembly 123 above compensating diaphragm 159.

An exhaust valve, indicated in general as at 171, leads from compensating chamber 169 and comprises a cylindrical portion 173 slidably mounted in a cylinder 175 for upward and downward movement therein. The lower end of cylindrical portion 173 is reduced in diameter to establish an annular passage 177 between the reduced portion and the cylinder 175 and is provided on the lower face thereof with a circular composition piece 179 which seats on an annular shoulder 181 provided in housing assembly part 133 to close the valve, as shown in FIG. 4.

A cap 183 having an exhaust port 185 therethrough is threadedly engaged on the upper end of housing assembly part 133 to cover the upper end of cylinder 175 and limit upward movement of cylindrical portion 173.

When diaphragm follower 135 is moved upwardly in a manner later to be described, the upper end thereof contacts cylindrical portion 1'73 to move it upwardly and unseat piece 179 from shoulder 181 so that the outside atmosphere is connected to compensating chamber 169 through exhaust port 185, through the passage 187 in portion 173, and through annular passage 177 and into the compensating chamber.

A vacuum supply valve 189 has piece 179 in common with the exhaust valve 171 and, in addition to this piece, the vacuum supply valve comprises the upper end of diaphragm follower 135 which is tapered upwardly and inwardly to the uppermost end thereof to establish a thin annular seating surface 191 which surrounds the upper end of a passage 193 that communicates with compensating chamber 169 when the valve is open and extends downwardly through the diaphragm follower 135 and laterally through the side of the diaphragm follower into vacuum chamber 165. When seating surface 191 is in contact with piece 179, in a manner later to be described, it will be understood that vacuum supply valve 189 is closed to cut off communication between compensating chamber 169 and vacuum chamber 165. This arrangement of the common part, i.e. the piece 179, of the exhaust valve 171 and the vacuum valve 189, is of importance in controlling theditferential between the time one valve will close and the other will open. This, of course, is true in the reverse order, i.e. as one valve closes the other will start to open with additional movement of the diaphragm follower 135. Also, the thin seating surface 191 is of importance in facilitating the unseating of the vacuum supply valve 189.

Speed selector 37 comprises an enclosed assembly 1% including a body 197 and a cover 199 fixedly attached thereto as by screws 291 or the like. A substantially circular flexible diaphragm 203 divides the interior of assembly 195 into a first chamber 2% and a second chamber 207. Diaphragm 2613 is preferably clamped adjacent its outer periphery between body 197 and cover 199 and extends inwardly where it is attached to the inner end of a shaft 209 by suitable means as, for example, by the diaphragm being clamped between the flange of a piece 213 and a nut 215 threadedly engaged on a reduced portion 127 of piece 213. Piece 213 is connected to the inner end of shaft 209 in any suitable well-known manner so that the shaft can rotate relative to the piece and yet any endwise movement of the shaft will carry the piece therewith. Shaft 209is threaded intermediate the ends thereof as at 219 where it threadedly extends through a threaded opening in cover 19? and to the outer end of the shaft is fixedly mounted a handle 221 for rotating the shaft. Handle 221 is provided with a pointer 223 which is adapted to be positioned opposite indicia 225 to indicate the speed setting of the handle. Assembly 195 is preferably mounted on the backside of the dashboard 227 of the automobilewith shaft 2119 extending through an opening in the dashboard and with the handle 221 and the dial 22? carrying indicia 225 being on the front side of the dashboard.

Various ports and conduits and other connections of the speed sensor 35, speed selector 37, and actuator 39 are as follows: A port 23-1 extends through cover 199 to communicate first chamber 205 with the outside atmosphere. A port 233 in body 197 enters into second chamber 2117 and is communicated with a port 235 in housing part 127 .by a conduit 237 so that second chamber 207 is communicated with hydraulic chamber 163. The ends of conduit 237 are connected to the respective parts above described by suitable well-known means. The space defined by second chamber 207, conduit 237 and hydraulic chamber 163 is substantially filled with a suitable liquid as a hydraulic fluid and has a minor unfilled portion to act as an air head to permit a small amount of compressibility. A port 239 in housing assembly part enters into 'lower chamber 161 and is connected by a conduit 241 to the conventional engine water pump indicated diagrammatically as at 243 so that the pressure from the water pump is felt in lower chamber 161 and this pressure varies in direct proportion to the engine speed. A port 245 in housing assembly part 129 which enters into vacuum chamber 165 has connected thereto one end of a conduit 247 which leads to a vacuum accumulator 249. Vacuum accumulator 249 is simply a large enclosed chamber 251 which dampens out variations in the vacuum. Another conduit 253 interconnects chamber 251 with the intake manifold 255 of the automobile engine and interposed in conduit 253 is a check valve 257. A port 259 in housing assembly part 131 enters into atmospheric chamber 167 and exhausts to the atmosphere through conduit 261. A port 263 in housing assembly part 133 enters into compensating chamber 169 and is connected by a conduit 265 to a port 267 in diaphragm housing half 61 which enters into head chamber 75 to communicate the head chamber with the compensating chamber.

The electrical control circuit 43 of the present invention is best shown in FIG. 2 and is described as follows: The electrical control circuit includes electro-magnetic coil 15 heretofore described, one end of which coil is connected through an electrical connector 263 to one contact of a two contact push-button switch 269 as by a lead 271. The other contact of switch 269 is connected to a normally open relay switch 273 by a lead 275. Relay switch 273 is part of a relay 277 and is adapted to close upon energization of the relay. The other contact of relay'switch 273 is connected to eleotro-magnetic coil 45 as by a lead 279, through a suitable electrical connector as at 280. Lead 275 is connected by a lead 281 to one side of the coil of relay 277, the other side of the coil being connected by a lead 233 to a switch 285, which in turn is grounded. Switch 285 is normally disposed in a closed disposition and is opened by depression of brake pedal 287 of the automobile. Switch 285, which is schematically shown in FIG. 2 by the conventional symbol for a switch, is preferably physically constructed by using, as a part of the switch, brake arm 2S9 which is made of metal and is grounded. Thus, lead 283 is connected to a conductor 291 which is movably supponted from fioor board 11 by bracket 293 insulated from floor board 11 as at 295, the conductor being adapted for limited upward and downward movement through an aperture in the bracket. A spring 297 connected at one end to bracket 293 andat the other end to conductor 291 urges'conductor 291 downwardly to insure a good connection between the conductor and brake arm 289 when the brake is in an upward or non-depressed disposition. It will be understood that when brake pedal 287 is depressed, arm 239 moves downwardly away from conductor 291, thereby breaking the circuit.

One conductor of an indicator lamp 299 is connected to lead 275 as by a lead 301 and the other conductor of the lamp is connected to ground as by a lead 303. One contact of a main switch 305, which is preferably a toggle type of switch, is connected to lead 271 as by a lead 307. The other contact of main switch 305 is connected by a lead 309 to a source of electrical power as a battery 311, the other side of the battery being grounded. A fuse 313 is preferably interposed in lead 309.

From the foregoing description of circuit 43, it will be understood that the circuit is arranged as follows: For the sake of clarity, coil 45, relay switch 273, and push- 4 button switch 269 will be hereinafter referred to as a group of electrical components. Said group of electrical components is arranged in series with the coil of relay 277 and battery 311. Within said group of electrical components, electro-magnetic coil 45 is arranged in series with relay switch 273 and push-button switch 269 is in parallel with this series arrangement of electro-magnetic coil 45 and relay switch 273.

With main switch 305 closed and with brake pedal 287 in the upward or non-depressed position, actuator 39 may be activated by pressing push-button switch 269. This action is as follows: When push-button switch 269 is momentarily depressed, current flows from battery 311 through lead 309, switch 305, lead 207, switch 269, lead 275, lead 281, the coil of relay 277, lead 283, switch 285, and thence to ground. Current also flows through the light 299 to cause the light to glow brightly. The current flowing through the coil of relay 277, as heretofore described, causes relay switch 273 to close, thereby completing a holding circuit through the coil of the relay which will cause the relay to remain energized even though switch 269 is released. This holding circuit includes the following: switch 285, lead 283, coil of relay 277, lead 281, relay switch 273, lead 279, electrO-magnetic coil 45, lead 271, lead 307, switch 305, lead 309, battery 311, and through ground back to switch 285. it will be understood that, when push-button switch 269 is released, light 299 will not glow as brightly as when the push-button switch is depressed since the current, when the switch is released, must also flow through electromagnetic coil 45 and switch 273.

The energizing of electromagnetic coil 45, upon momentary depression of push-button switch 269, causes a magnetic field to be set up around coil 45. It will be understood that this magnetic field will be concentrated by plungers 69 and 87 and when plunger 87 is brought into proximity with plunger 69 by pressure on accelerator pedal 13, it will cause the plunger 87 to be drawn into abutment With plunger 69.

It will be understood that when plunger 87 is in abutment with plunger 69, as above described, the position of the plunger 69 will determine the speed at which the motor of the vehicle is set. Thus, with plunger 69 disposed in the left part of sleeve 47, as viewed in FIG. 4, the speed of the motor will be set at a high speed and if the coil were positioned to the right, as viewed in this figure, the motor would be set at a low speed. In addition, it will be understood that with the speed set as above described, the driver may advance the accelerator independently of the actuator 39 since the advance or depression of the accelerator pedal 13 will cause rod 103 to move to the left as shown in FIGS. 1 and 4, which will be free to so move against the pressure of spring 99. Thus, the present device has this safety feature which permits sudden bursts of speed without having to disengage the actuator 39. Also, it will be understood that when the need for the increase in speed is over and the accelerator pedal is released, the actuator 39 will again hold the accelerator at the speed previously set.

In describing the manner in which the device 33 of the present invention regulates the speed of the vehicle, it is assumed that the device is in operation and button 269 has been depressed, as heretofore described. Also, it will be assumed that handle 221 is turned to a higher speed setting. It should be pointed out here that turn of handle 221 to a higher speed setting will cause shaft 209 to move to the right, as viewed in FIG. 4, and by the same token turn of the handle to a lower speed setting will cause the shaft 209 to move to the left, as viewed in this figure. Continuing with the description of the operation of the device, with the movement of handle 221 towards a higher speed setting the movement of shaft 209 will carry diaphragm 203 to the right and reduce the volume of the second chamber 207 thereby increasing the pressure in second chamber 207, conduit 237 and bydraulic chamber 163. This higher pressure acting on operating diaphragm 145 will cause downward movement of the diaphragm carrying with it diaphragm follower 135. It is also assumed in the description of this operation that the previous setting of the speed has been such that vacuum supply valve 189 is closed. The above mentioned downward movement of diaphragm follower 135 causes vacuum supply valve 189 to open which in turn will cause compensating chamber 169 to be communicated with vacuum accumulator 249 and thus reduce the pressure in the compensating chamber and the pressure in head chamber 75 below atmospheric pressure. Atmos pheric pressure in chamber 77 acting on the right side of diaphragm 67 will cause the diaphragm to move towards the left, as viewed in FIG. 4, which will carry with it the inner plunger 69. Since the device is in operation, the magnetic field of coil 45 will have been established and consequently outer plunger 87 will be in abutment with inner plunger 69 and the leftward movement of the inner plunger will carry with it .the outer plunger which will in turn cause the fuel valve to open and give the engine more fuel, in a manner as heretofore described. As' more power is developed, the speed of the vehicle will increase. This increase in speed in turn causes the water pump 243 to deliver a higher pressure which will act on the underside of the operating diaphragm 145. When the pressure on the underside of operating diaphragm 145 exceeds the pressure on the upper side of this diaphragm, the diaphragm follower 135 will be carried upwardly to cause closing of vacuum supply valve 189. This will trap a given pressure in compensating chamber 169 and head chamber '75 to hold the actuating diaphragm 67 in a given position which corresponds to a given speed of the vehicle.

With the above conditions existing as the vehicle is cruising over a level road, it is assumed that the vehicle then starts up a hill. As the vehicle starts up the hill, the speed would tend to decrease because the power being developed was at a constant rate at the time of approach to the hill. This decrease in speed of the vehicle is reflected in a lower water pressure being delivered and acting on the underside of operating diaphragm 145. As a result of this, the forces would be unbalanced and the pressure in hydraulic chamber 163 acting on the upper side of the operating diaphragm forces the operating diaphragm downward causing the vacuum supply valve 189 to open and further reduce the pressure in the compensating chamber 169 and the head chamber 75. Under this condition, the diaphragm 67 will move to the left, as viewed in FIG. 4, carrying with it the heretofore mentioned connections to the accelerator linkage allowing more fuel to be delivered to the engine and more power would be developed therein to compensate for the speed decrease due to the inclined road or hill. Even though the speed of the vehicle would not return to the exact speed to which it was at the time of approach, the additional reduction of pressure within the compensating chamber 169 would again act to reclose the vacuum supply valve 109 and trap this new lower pressure within the head chamber 75. In other words, the function of the compensating diaphragm 159 is such that it will only allow a given power increase for a given speed decrease and then it follows that it will allow a corresponding power decrease for a given speed increase. It should beobvious that the device is not intended for compensation.

As the vehicle starts its descent from the hill, the speed will increase. As a result of this increase, the increased water pressure acting on operating diaphragm 145 will cause the diaphragm to move upwardly forcing diaphragm follower to move further upwardly (note that the diaphragm follower was heretofore in a position to close vacuum supply valve 189), which further upward movement causes exhaust valve 171 to open, thus allowing atmospheric pressure to enter compensating chamber 169 and head chamber 75. The resulting higher pressure will cause diaphragm 67 to move to the right, as viewed in FIG. 4, resulting in decreased power due to less fuel being delivered to the engine. As a result of less power being developed, the vehicle speed will return to or near its original level ground speed at which the water pressure being developed will balance with the force on the upper side of the operating diaphragm 145 and allow the diaphragm to return to its mid-position, at which point both the vacuum supply valve 189 and exhaust valve 171 will be closed and the pressures acting on compensating diaphragm 159 and actuating diaphragm 67 will return to or near the original condition that existed when the vehicle was cruising on level ground. Here again, the effect of the compensating diaphragm 159 is demonstrated in that it always opposes the last change in the position of the operating diaphragm 145. Just as it tends to prevent overacceleration, it tends to prevent overdeceleration. The total effect of the compensating diaphragm 159 could be varied at the time of assembly by changing the ratio of the area of it to that of the operating diaphragm 145. The operating diaphragm 145, however, should always be the greater in area.

It should be understood that if the vehicle were cruising at a given speed, the rate of speed could be decreased merely by operating the speed selector 37 in a direction opposite to that mentioned at the beginning of previous example given. Of course, the events would occur in the reverse order.

It should be pointed out that the forces that tend to return the accelerator to the idle speed direction are the normal and usual spring 29 that is associated with the normal accelerator mechanism plus the additional spring 85. The specific purpose of spring 35 is to urge diaphragm 67 towards its extreme low speed position when both sides are Vented to the atmosphere and the Weight of the accelerator is no longer acting as would be the case when the magnetic field is discharged.

The arrangement heretofore described is intended for an internal combustion engine that would normally have a vacuum associated with the intake manifold, but it should be understood that this device could equally as well be adapted to internal combustion engines that make use of super-charging of the intake air manifold as is common on vehicles motivated by diesel engines as used on trucks, buses, and the like.

From the foregoing description it will be apparent that a very unique and effective mechanism is provided for automatically controlling the speed of a vehicle engine. In addition, it will be apparent that there is no danger of accidental engagement of the device because any time the speed of the vehicle is below the setting of the speed selector 3'7, diaphragm 67 and plunger 69 will be well out of range of engagement unless the accelerator is de pressed to a point well beyond that necessary or common for ordinary maneuvering of the vehicle. Furthermore, it will be apparent that the device of the present invention is so designed for ease of adaptation by utilizing existing facilities of the vehicle, such as water pressure, manifold pressure, battery power, etc.

Although the invention has been described and illustrated with respect to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes and modifications may be made therein which are within the full intended scope of this invention as hereinafter claimed.

1 claim:

1. A control mechanism for controlling the speed of the engine of a motor vehicle having a throttle and having means biasing said throttle towards a speed decreasing direction, said control mechanism comprising a sleeve, an electro-magnetic coil disposed around said sleeve, an inner plunger slidably mounted in said sleeve, an outer plunger slidably mounted in said sleeve and adapted for movement into and out of abutment with said inner plunger, said outer plunger being provided with an outwardly opening chamber, electrical circuit means coupled to said elect-ro-magnetic coil to energize the coil and establish a magnetic field therearound, means coupling said outer plunger and said throttle, said outer plunger being held in contact with said inner plunger by said magnetic field whereby holding said throttle at a set engine speed; said coupling means for said plunger and said throttle being arranged to permit independent advance of said throttle relative to said outer plunger and comprising a retaining ring removably mounted in said chamber, a follower slidably mounted in said chamber inwardly of said retaining ring, a rod fixedly mounted on said follower adjacent one end of the rod and extending outwardly from the follower, and means operably linking said rod adjacent the other end thereof to said throttle; actuator means coupled to said inner plunger for setting the position of the inner plunger, speed selector means for selecting the desired speed of the vehicle, pump means responsive to the speed of the engine of the vehicle and substantially directly proportional thereto, speed sensor means responsive to said speed selector means and said pump means and coupled to said actuator means for operating said actuator means to position said inner plunger.

2. The control mechanism in accordance with claim 1 in which said circuit means comprises a relay including a relay coil and a normally open relay switch adapted to be closed upon the energizing of said relay coil; a source of electrical power; a group of electrical components including said electro-magnetic coil, said relay switch and a normally open push-button switch; said group of electrical components being in series with said relay coil and said source of electrical power, said group of electrical components being arranged with said electro-magnetic coil in series with said relay switch and with said push-button switch in parallel with the series arrangement of said electro-rnagnetic coil and relay switch.

3. A control mechanism for controlling the speed of the engine of a motor vehicle having a throttle and having means biasing said throttle towards a speed decreasing direction, said control mechanism comprising a sleeve, an electro-magnetic coil disposed around said sleeve, an inner plunger slid-ably mounted in said sleeve, an outer plunger slidably mounted in said sleeve and adapted for movement into and out of abutment with said inner plunger, electrical circuit means coupled to said electromagnetic coil to energize the coil and establish a magnetic field there-around, means coupling said outer plunger and said throttle, said outer plunger being held in contact with said inner plunger by said magnetic field whereby holding said throttle at a set engine speed; said coupling means for said plunger and said throttle being arranged to permit independent advance of said throttle relative to said plunger; actuator means coupled to said inner plunger for setting the position of the inner plunger, speed selector means for selecting the desired speed of the vehicle, pump means responsive to the speed of the engine of the vehicle and substantially directly proportional thereto, speed sensor means responsive to said speed selector means and said pump means and coupled to said actuator means for operating said actuator means to position said inner plunger.

4. A control mechanism for controlling the speed of the engine of a motor vehicle having a throttle, said control mechanism comprising a sleeve, an electro-magnetic coil disposed around said sleeve, an inner plunger slidably mounted in said sleeve, an outer plunger slidably mounted in said sleeve and adapted for movement into and out of abutment with said inner plunger, electrical circuit means coupled to said electro-magnetic coil to energize the coil and establish a magnetic field there-around, means coupling said outer plunger and said throttle, said outer plunger being held in contact with said inner plunger by said magnetic field whereby holding said throttle at a set engine speed, means establishing a head chamber including an actuating diaphragm defining a Wall of said head chamber; said inner plunger and said diaphragm being connected whereby pressure in said head chamber determines the position of said inner and outer plungers and the setting of said throttle.

5. A control mechanism for controlling the speed of the engine of a motor vehicle having a throttle and hav- 7 12. by holding said throttle at a set engine speed, and actuator means coupled to said inner plunger for setting the position of said inner plunger.

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1. A CONTROL MECHANISM FOR CONTROLLING THE SPEED OF THE ENGINE OF A MOTOR VEHICLE HAVING A THROTTLE AND HAVING MEANS BIASING SAID THROTTLE TOWARDS A SPEED DECREASING DIRECTION, SAID CONTROL MECHANISM COMPRISING A SLEEVE, AN ELECTRO-MAGNETIC COIL DISPOSED AROUND SAID SLEEVE, AN INNER PLUNGER SLIDABLY MOUNTED IN SAID SLEEVE, AN OUTER PLUNGER SLIDABLY MOUNTED IN SAID SLEEVE AND ADAPTED FOR MOVEMENT INTO AND OUT OF ABUTMENT WITH SAID INNER PLUNGER , SAID OUTER PLUNGER BEING PROVIDED WITH AN OUTWARDLY OPENING CHAMBER, ELECTRICAL CIRCUIT MEANS COUPLED TO SAID ELECTRO-MAGNETIC COIL TO ENERGIZE THE COIL AND ESTABLISH A MAGNETIC FIELD THEREAROUND, MEANS COUPLING SAID OUTER PLUNGER AND SAID THROTTLE, SAID OUTER PLUNGER BEING HELD IN CONTACT WITH SAID INNER PLUNGER BY SAID MAGNETIC FIELD WHEREBY HOLDING SAID THROTTLE AT A SET ENGINE SPEED; SAID COUPLING MEANS FOR SAID PLUNGER BY SAID THROTTLE BEING ARRANGED TO PERMIT INDEPENDENT ADVANCE OF SAID THROTTLE RELATIVE TO SAID OUTER PLUNGER AND COMPRISING A RETAINING RING REMOVABLY MOUNTED IN SAID CHAMBER, A FOLLOWER SLIDABLY MOUNTED IN SAID CHAMBER INWARDLY OF SAID RETAINING RING, A ROD FIXEDLY MOUNTED ON SAID FOLLOWER ADJACENT ONE END OF THE ROD AND EXTENDING OUTWARDLY FROM THE FOLLOWER, AND MEANS OPERABLY LINKING SAID ROD ADJACENT THE OTHER END THEREOF TO SAID THROTTLE; ACTUATOR MEANS COUPLED TO SAID INNER PLUNGER FOR SETTING THE POSITION OF THE INNER PLUNGER, SPEED SELECTOR MEANS FOR SELECTING THE DESIRED SPEED OF THE VEHICLE, PUMP MEANS RESPONSIVE TO THE SPEED OF HE ENGINE OF THE VEHICLE AND SUBSTANTIALLY DIRECTLY PROPORTIONAL THERETO, SPEED SENSOR MEANS RESPONSIVE TO SAID SPEED SELECTOR MEANS AND SAID PUMP MEANS AND COUPLED TO SAID ACTUATOR MEANS FOR OPERATING SAID ACTUATOR MEANS TO POSITION SAID INNER PLUNGER. 